Abstract WP113: Stroke in the Young: Sex Differences in Risk Factors, Etiologies, Acute Treatments, and Outcomes in a Nationwide Analysis

Introduction: Stroke in the young (SITY), defined as acute ischemic stroke (AIS) in patients aged 18–50, is a growing public health concern with unique etiologic and clinical features. Sex differences in vascular risk profiles, stroke etiologies, treatments, and outcomes in SITY remain poorly understood. Methods: Using the 2022 National Inpatient Sample, we identified all adult AIS patients aged 18-50 using ICD codes and stratified them by sex. Risk factors, acute treatments, stroke etiologies, and outcomes were compared between sexes using survey-weighted analysis. Results: Of the 64,110 SITY hospitalizations, 54.0% were male. Females had lower rates of hypertension (61.3 vs 67.7%) and hyperlipidemia (36.5 vs 40.7%), but higher rates of obesity (30.3 vs 24.4%) ( all p <0.0001). Smoking was more common in males (34.3 vs 27.2%, p <0.0001). Stroke etiologies differed significantly by sex, with males having a higher incidence of atrial fibrillation (6.5% vs 4.4%, p <0.0001) and left ventricular thrombus (2.4% vs 1.4%, p <0.0001). Females had higher prevalence of extracranial carotid atherosclerosis (11.1 vs 8.4%), atrial/AV septal defects (8.8 vs 7.5%), antiphospholipid syndrome (2.4 vs 1.2%), other hypercoagulable states (6.5 vs 3.8%), and moyamoya disease (2.2 vs 0.8%) (all p <0.01). Acute treatments differed, with males being 9% less likely to receive IV thrombolysis compared to females (12.9% vs 14.4%, p=0.01). Rates of mechanical thrombectomy were similar (6.7 vs 7.3%). Females had a slightly shorter hospital stay (-0.81 days, 95% CI -1.4 to - 0.3). Hospital mortality was higher in males (6.9 vs 5.7%, p <0.001), corresponding to a 21% greater risk of death. Complications such as hemorrhagic transformation (7.9 vs 6.6%), sepsis (11.3 vs 9.8%), and pneumonia (9.8 vs 8.1%) were also more common in males ( all p <0.01). Conclusions: In this nationally representative cohort of SITY, we identified important sex differences in stroke risk factors, etiologies, acute treatment patterns, and hospital outcomes. We found that young males represent the majority of SITY cases and experience longer hospital stays with more frequent complications. They are also 9% less likely to receive IV thrombolysis and have a 21% greater risk of death compared to young females. These findings underscore the need for future studies to better understand the biological, social, and systems-level drivers of these disparities in SITY.